Image projection device

Abstract

An image projection device can comprise a light source configured to output light corresponding to an image, and an optical system disposed in front of the light source and configured to project the image. The light source can comprise a substrate comprising a plurality of pixels and a plurality of semiconductor light emitting devices in the plurality of pixels of the substrate, respectively. The substrate can be disposed to be inclined with respect to the optical system, and the semiconductor light emitting device can emit a first condensed light having a first beam angle inclined with respect to the substrate.

1 . An image projection device, comprising:
 a light source configured to output light corresponding to an image; and   an optical system disposed in front of the light source and configured to project the image,   wherein the light source comprises:   a substrate comprising a plurality of pixels; and   a plurality of semiconductor light emitting devices in the plurality of pixels of the substrate, respectively,   wherein the substrate is disposed to be inclined with respect to the optical system, and   wherein the semiconductor light emitting device is configured to emit a first condensed light having a first beam angle inclined with respect to the substrate.   
     
     
         2 . The image projection device of  claim 1 , wherein the first condensed light emitted at the inclined first beam angle is configured to be perpendicularly incident on the optical system. 
     
     
         3 . The image projection device of  claim 1 , wherein the light source comprises an electrode disposed on the substrate and spaced apart from the semiconductor light emitting device. 
     
     
         4 . The image projection device of  claim 3 , wherein the semiconductor light emitting device has a first isosceles triangle having a first-first side surface, a first-second side surface and a first-third side surface, the first-first side surface and the first-second side surface having the same length, and the first-third side surface having a length different from the first-first side surface or the first-second side surface. 
     
     
         5 . The image projection device of  claim 4 , wherein the first condensed light is configured to be emitted at the first beam angle inclined with respect to the substrate through the first-third side surface. 
     
     
         6 . The image projection device of  claim 4 , wherein the first isosceles triangle has a first vertex angle between the first-first side surface and the first-second side surface, and
 the first vertex angle is 90 degrees to 150 degrees.   
     
     
         7 . The image projection device of  claim 4 , wherein the first isosceles triangle of the semiconductor light emitting device has a first vertex point where the first-first side surface and the first-second side surface meet,
 the first vertex point is located on a center line crossing the center of the electrode, and   the first vertex point is located closer to the electrode than the first-third side surface.   
     
     
         8 . The image projection device of  claim 4 , wherein one side surface of the electrode has a different separation distance from the entire surface of each of the first-first side surface and the first-second side surface. 
     
     
         9 . The image projection device of  claim 4 , wherein one side surface of the electrode has the same separation distance from the entire surface of each of the first-first side surface and the first-second side surface. 
     
     
         10 . The image projection device of  claim 3 , wherein the light source comprises a lens surrounding the semiconductor light emitting device, and
 the lens is configured to emit a second condensed light having a second beam angle inclined with respect to the substrate.   
     
     
         11 . The image projection device of  claim 10 , wherein the lens has a second isosceles triangle having a second-first side surface, a second-second side surface and a second-third side surface, the second-first side surface and the second-second side surface having the same length, and the second-third side surface having a length different from the second-first side surface or the second-second side surface. 
     
     
         12 . The image projection device of  claim 11 , wherein the second condensed light is configured to be emitted at the second beam angle inclined with respect to the substrate through the second-third side surface. 
     
     
         13 . The image projection device of  claim 11 , wherein the second isosceles triangle has a second vertex angle between the second-first side surface and the second-second side surface, and
 the second vertex angle is 90 degrees to 150 degrees.   
     
     
         14 . The image projection device of  claim 11 , wherein the second isosceles triangle of the lens has a second vertex point where the second-first side surface and the second-second side surface meet,
 the second vertex point is located on a center line crossing the center of the electrode,   The second vertex point is located closer to the electrode than the first-third side surface.   
     
     
         15 . The image projection device of  claim 11 , wherein one side surface of the electrode has a different separation distance from the entire surface of each of the second-first side surface and the second-second side surface. 
     
     
         16 . The image projection device of  claim 11 , wherein one side surface of the electrode has the same separation distance from the entire surface of each of the second-first side surface and the second-second side surface. 
     
     
         17 . The image projection device of  claim 3 , wherein the semiconductor light emitting device comprises a first semiconductor light emitting device and a second semiconductor light emitting device,
 the electrode comprises a first electrode disposed on one side of the first semiconductor light emitting device and a second electrode disposed between the first semiconductor light emitting device and the second semiconductor light emitting device, and   the first semiconductor light emitting device is spaced apart from the second electrode by a distance L or more according to Equation 1.
     L=H /tan θ  [Equation 1]
 
   H: Height of the second electrode   θ: Beam angle of condensed light emitted from the first semiconductor light emitting device   
     
     
         18 . The image projection device of  claim 1 , wherein the light source comprises:
 an insulating layer surrounding the semiconductor light emitting device; and   a connection electrode disposed on the insulating layer and configured to connect the electrode and the semiconductor light emitting device.   
     
     
         19 . The image projection device of  claim 1 , wherein the semiconductor light emitting device has a side surface having an area larger than the area of an upper surface. 
     
     
         20 . The image projection device of  claim 1 , wherein the semiconductor light emitting device comprises at least one or more of a red semiconductor light emitting device, a green semiconductor light emitting device, and a blue semiconductor light emitting device.